Samsung has appointed a new smartphone boss as it looks to retain its crown as the world's number one smartphone supplier, according to Bloomberg.

In the company's annual exec reshuffle, Roh Tae-moon was promoted from head of research for Samsung's mobile business to the head of its entire smartphone operations.

Meanwhile, the company's three joint CEOs - Kim Ki-nam, vice chairman and CEO of its semiconductor business; Kim Hyun-Suk, CEO of its consumer electronics business; and DJ Koh, CEO of its mobile business - have all retained their leadership roles.

The Korean tech giant has promoted Roh at a time of stiff competition from Huawei, and cheap Chinese rivals like Oppo. Samsung remains the world's biggest smartphone maker and has managed to grow it share of the market, but overall there's greater competition from firms like Huawei and there is fear of "peak smartphone" as demand weakens.